The projects discussed in this paper, Galileo and ITER, are two contrasting experiences of Euro-Asian cooperation within Very Large (Public) Scientific Enterprises. They offer key insights into the deepening relations which have given shape to the rapidly expanding field of Euro-Asian collaborative interregional projects. Cooperative agendas within such "Big Science" endeavors heighten the question of the political considerations supporting the decision to engage specific forms of international cooperation. As the main driving force behind both projects, the EU's choices have resulted in the establishment of novel and distinct forms of Euro-Asian scientific cooperation. A better understanding of how such Euro-Asian initiatives emerge can logically be garnered by confronting the Euro-Chinese cooperation within Galileo, and the Euro-Japanese partnership within ITER. This comparison will show that the agendas and institutions of these two interregional policies vary greatly. Within the same policy field-in casu Large Scientific Projects-and in relationship to the same region-i.e. East Asia-this study shows that fundamentally different policies are practiced side-by-side. If in both cases Euro-Asian scientific cooperation has provided its participants with renewed leverage and unprecedented opportunities, the exact scope and function of these interregional collaborations range from the merely tactical in the Euro-Chinese Galileo experience, to the substantial in the Euro-Japanese ITER experience. © Springer Science+Business Media B.V. 2010.